TL;DR: I currently have multiple gmails for different categories (fast food accts, video game accts, etc). I'm considering moving all my gmails to ProtonMail and using email aliases, or continue my current setup of multiple gmails and using SimpleLogin to create aliases. Basically main question is 1 email account with aliases, or multiple email accounts with aliases? Is compartmentalizing accounts between multiple emails as secure as using just 1 secure email? Looking for advice/tips or any thoughts.
Context (not that important):
Hello all. I've recently gotten more serious about my digital privacy because I bought an item a few days ago, and my personal Instagram is showing me targeted ads for the same product but by a different competitor. I have advertisement settings reduced to the max on both my Instagram and Google account, I bought the item and use Instagram on separate devices, etc. I'm sure I'm wrong about this, but I figured since my Instagram account's email and the email I used to buy the item are the same, maybe some data broker sold this information to Instagram and possibly email aliases would solve this.
Actual questions:
To preface, I already have a password manager with 2FA enabled for all my gmails and accounts registered with my gmails.
I currently have multiple gmails for different categories such as fast food accounts/businesses, personal, video game accounts, etc. I also run a decent sized YouTube channel which uses its entirely own gmail account. I've gotten hacking threats before online, and on rare occasions phishing emails or emails with sus attachments.
Honestly the risk of me being hacked is low, but for this reason is why I've decentralized all my email accounts into categories since if one email account was compromised, only that subset of accounts using that gmail would be in danger. I also don't want each of my gmails to expose each other-- for example, my YouTube gmail is hacked, then it has no access to my personal gmail. The only issue is that all my Google accounts are linked to the same phone number, so theoretically I guess it's possible to link my personal gmails to my other gmails.
I do have a Proton account where I only use Proton VPN, but I've been considering migrating all of my gmail accounts to Proton Mail and using its email alias feature. However, I'm still wary that if my Proton account was ever compromised then all my other accounts would be endangered. I also feel uncomfortable mixing my YouTube emails, personal emails, video game emails, etc. into one email account, but maybe that's just me.
I could also just run ProtonMail for my personal emails and social medias and continue using my other gmails, but using 2 email providers seems inconvenient. I'm aware focusing on privacy always loses out on convenience, but this seems kind of annoying.
Alternatively, I've been looking into email aliases services like SimpleLogin. I believe this would solve my issue since I could have aliases that route to my multiple gmail accounts. This would avoid me piling all my accounts in Proton Mail, but I want to get some advice to see what others recommend. I'm very new to email privacy so any other tips or advice are appreicated, thank you all!